使用适用于 .NET 的 Google API 访问用户信息

Question

我正在使用 Google API 预览版 (1.7.0) 通过 OAuth2 授权用户。我一直在关注sample MVC code。这是我对FlowMetadata的实现：

private static readonly IAuthorizationCodeFlow flow = ...; // Implementation of tokens

public static async Task<Google.Apis.Auth.OAuth2.Web.AuthorizationCodeWebApp.AuthResult> GetCredentials(Controller controller, CancellationToken cancellationToken) {
    var result = await new AuthorizationCodeMvcApp(controller, new Models.Generic.AppFlowMetadata()).AuthorizeAsync(cancellationToken);
    if (result.Credential != null)
    {
         // Struggling here. How do I make a request to get the e-mail address?
    }
}

我现在有一个有效的UserCredential 和访问令牌，但我找不到任何用于访问用户信息的托管 API。我确实找到了this question，但这似乎假设我只是提出原始请求，而不是使用官方库。

如何获取用户的电子邮件地址？

Answer 1

您应该执行以下操作：

1. 除了 Google.Apis.Auth NuGet 包之外，您还应该安装以下页面：https://www.nuget.org/packages/Google.Apis.Oauth2.v2

2. 将 Google.Apis.Oauth2.v2.Oauth2Service.Scope.UserinfoProfile 和 Google.Apis.Oauth2.v2.Oauth2Service.Scope.UserinfoEmail 添加到范围列表（当您初始化 AppFlowMetadata 时）。

3. 现在，添加以下代码：

if (result.Credential != null)
{
    var oauthSerivce = new Google.Apis.Oauth2.v2.Oauth2Service(
        new BaseClientService.Initializer()
        {
            HttpClientInitializer = credential,
            ApplicationName = "OAuth 2.0 Sample",
        });

    var userInfo = await oauthSerivce.Userinfo.Get().ExecuteAsync();
    // You can use userInfo.Email, Gender, FamilyName, ... 
}

Answer 2

将范围设置为：

• https://www.googleapis.com/auth/userinfo.email
• https://www.googleapis.com/auth/userinfo.profile

在：Google.Apis.Auth.OAuth2.Flows.AuthorizationCodeFlow.Scopes

并使用这个端点地址：https://www.googleapis.com/oauth2/v1/userinfo?alt=json

这应该可以帮助您获取所需的信息。

Answer 3

在这里，我编辑我的答案。请调查一下。在 Default2.aspx 页面上，我在标签中显示 Session["username"] 和 Session["useremail"] 值。我希望这些对你有帮助。

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using DotNetOpenAuth.OpenId;
using DotNetOpenAuth.OpenId.RelyingParty;
using DotNetOpenAuth.OpenId.Extensions.SimpleRegistration;
using DotNetOpenAuth.OpenId.Extensions.AttributeExchange;

public partial class _Default : System.Web.UI.Page 
{

   protected void Page_Load(object sender, EventArgs e)
   {

       openIdAuth();

   }

   protected void openIdAuth()
  {
       OpenIdAjaxRelyingParty rp = new OpenIdAjaxRelyingParty();
       var response = rp.GetResponse();

       if (response != null)
       {
         switch (response.Status)
         {
            case AuthenticationStatus.Authenticated:
                NotLoggedIn.Visible = false;
                Session["GoogleIdentifier"] = response.ClaimedIdentifier.ToString();

                var fetchResponse = response.GetExtension<FetchResponse>();
                Session["FetchResponse"] = fetchResponse;
                var response2 = Session["FetchResponse"] as FetchResponse;

                string UserName = response2.GetAttributeValue(WellKnownAttributes.Name.First) ?? "Guest"; // with the OpenID Claimed Identifier as their username.
                string UserEmail = response2.GetAttributeValue(WellKnownAttributes.Contact.Email) ?? "Guest";

                Session["username"] = UserName;
                Session["useremail"] = UserEmail;

                Response.Redirect("Default2.aspx");
                break;

            case AuthenticationStatus.Canceled:
                lblAlertMsg.Text = "Cancelled.";
                break;

            case AuthenticationStatus.Failed:
                lblAlertMsg.Text = "Login Failed.";
                break;
        }

    }
    var CommandArgument = "https://www.google.com/accounts/o8/id";
    string discoveryUri = CommandArgument.ToString();
    OpenIdRelyingParty openid = new OpenIdRelyingParty();

    var url = new UriBuilder(Request.Url) { Query = "" };
    var request = openid.CreateRequest(discoveryUri); // This is where you would add any OpenID extensions you wanted
    var fetchRequest = new FetchRequest(); // to fetch additional data fields from the OpenID Provider

    fetchRequest.Attributes.AddRequired(WellKnownAttributes.Contact.Email);
    fetchRequest.Attributes.AddRequired(WellKnownAttributes.Name.First);
    fetchRequest.Attributes.AddRequired(WellKnownAttributes.Name.Last);
    fetchRequest.Attributes.AddRequired(WellKnownAttributes.Contact.HomeAddress.Country);
    request.AddExtension(fetchRequest);

    request.RedirectToProvider();
   }
 }

Answer 4

获取 UserProfile 数据的完整代码。

var secrect = new ClientSecrets()
{
    ClientId = "myClientId",
    ClientSecret = "mySecret"
};

var scopes = new[] { Oauth2Service.Scope.UserinfoEmail, auth2Service.Scope.UserinfoProfile };

UserCredential credential = GoogleWebAuthorizationBroker.AuthorizeAsync(secrect, scopes, "user", CancellationToken.None).Result;
    
var oauthSerivce = new Oauth2Service(new BaseClientService.Initializer()
{
    HttpClientInitializer = credential,
    ApplicationName = "MyApplicationName",
});

var userInfo = oauthSerivce.Userinfo.Get().Execute();